Portable devices are advantageous in having small sizes and being easy to carry, and accordingly are very popular with users.
During the development, manufacture, and use of a portable device, and in some special application environments, an external power source can be used to power an internal power and signal management subsystem (IPSMS), which is arranged on a printed circuit board (PCB) in the portable device. For example, in the process of manufacturing the portable device, it can be necessary to perform a performance test on a printed circuit board assembly (PCBA) in the portable device to ensure that the PCBA in the portable device to be presented to a user functions properly.
Currently, the external power source generally powers the IPSMS by means of a special cable and a special connector. As shown in FIG. 1, in a typical implementation, the external power source powers the IPSMS through a VBAT pin in a port of the portable device. The port of the portable device has seven pins (e.g., a VBUS pin, a D− pin, a D+ pin, two GND pins, and a VBAT pin). Since the VBAT pin is not a pin in accordance with universal serial bus (USB) specifications, the special cable and the special connector are required to connect the external power source with the port of the portable device. However, the special cable and the special connector have to be customized, adding cost and complication to the design of the IPSMS.